Grinding second gear

Discussion in '1955-1959' started by Dillon Hill, Jul 22, 2013.

  1. Dillon Hill

    Dillon Hill Member

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    Good day all
    Hope everyone is enjoying their summer driving these awsome trucks!
    My 59 has a three speed overdrive and shifting is becoming an issue. Shifting into second gear, both up and down, is grinding. The issue is worse the longer I drive. Starting out cold it doesn't do it, but before long it starts. Down shifting I can double clutch but the up shift is a bugger. Any help would be great.
    Thanks
    Mike
     
  2. ccharr

    ccharr Member

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    Sounds like it needs to be rebuilt ASAP
     
  3. AZ58Cameo

    AZ58Cameo Member

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    Charles, Didn't you get Two Transmissions From a Guy in Arizona?you could part with?
    OH Ya That was Me:)LOL
    Allen
     
  4. Bill Hanlon

    Bill Hanlon Member

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    Mike has a 3sp + OD trannym, so finding a replacement won't be easy.

    Sounds like it is time to go through the trans and replace the 2nd gear synchronizer parts.
     
  5. Dillon Hill

    Dillon Hill Member

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    I have no problem taking it apart to fix it over the winter, is the trans the same as a regular three speed w/od on the tail end? If so, the shop manual will take me thru it step by step. Also where to buy the parts?
     
  6. vwnate1

    vwnate1 Member

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    Gear Boinging

    First , take the time to do this simple test the next time it gets bad (heated up fully) :

    Standing still , engine idling , park brake firmly set , shift into first gear ~ did it grind or crunch , Y/N ? .

    Now , keeping the clutch to the floor , s-l-o-w-l-y shift from first into reverse then back again ~

    Did it crunch or grind this time Y/N ? .

    If yes , even one tiny "clink " as it changed , the clutch is the culprit or more likely the crankshaft's pilot bearing or bushing ~ it's worn out and oddly enough when they're worn out and floppy , they drag on the tranny's input (" First Motion " for out English Friends) shaft , this causes crunching into first and reverse and makes for rough up shifts .

    Of course , you already hot drained and re filled (slowly) the tranny with top quality synthetic gear oil , right ? .
     
  7. ccharr

    ccharr Member

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    I did not think they were OD's. How is the weather been up there lately Allen?


    Charles
     
  8. coilover

    coilover Member

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    Do what Nate said first but if it passes the test then it's about a 99.9% chance that it is the synchronizer drum. Also check the shift forks for wear while apart. When the oil is cold the brass clutch rings in the end of the drum will spin the drum at the same speed as the gear being shifted out of (synchronizing) but as the oil heats there is not as much of an oil layer between the brass and the tapered seat so there is slippage and the gears are spinning at different speeds--hence the grinding.
     
  9. vwnate1

    vwnate1 Member

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    Tranny Service

    IIRC ;

    The tranny proper uses the same innards ~ Dealer training taught us to disassemble & lay out all your old trannies on clean , light colored towels then measure , mix and match as you go ~

    Do not re use the bearings and if any wear on the cluster gear's shaft , no matter how slight , discard it .

    These are dead simple trannys , easy to overhaul in your driveway .

    Mind the proper shimming of the cluster gear ! Chevs Of The 40's in Washington State has all the seals and shims in stock .
     
  10. Dillon Hill

    Dillon Hill Member

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    The fluid is new and sythetic. I can shift from 1st to reverse and back with no grind.
    If the pilot bearing was bad, would it only cause the problem in second gear?
    I was at Chevy's of the 40's web site and they don't show the trany parts, they also only show up to 1954.
    Although I would like an older truck, right now I have to stick to the 59.(and I love it!)
     
  11. AZ58Cameo

    AZ58Cameo Member

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    Gee i always thought my 58 & 59 were Older Trucks:confused:
    Charles has two of my old three speeds but i would want to keep that overdrive
    too!
    Hope you can get it fixed!
    Good Luck,Allen
     
  12. Dillon Hill

    Dillon Hill Member

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    The original 3sp didn't stay in third gear, I replaced it with another 3sp and it turned out the syncros were bad in that one, couldn't down shift . Then this OD trany came along and it has been great! Nothing like having the extra gear.
    Anyway, can wait to get it straightened out.
    Thanks for the advice, I'll let you know how I make out.
    Mike
     
  13. vwnate1

    vwnate1 Member

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    Crunchy Gear Shifts

    No , the bad pilot bushing causes bad shifting in all gears , all the time , that's why the stationary testing is so important .

    I wish I had your pile 'O trannies ,it's pretty easy to build one good one out of several bad ones....

    My buddy Garnet's '58 needs a tranny , he got burned twice and is out of state so I can't help him . it's his late Father's old Work Truck .

    Part of being a Used Car / Junkyard Mechanic is learning to assemble good units from other's cast offs to keep the co$t$ down and the profit margin up .

    I'm sure you'll work it out in the end , I hope some one takes the left overs & puts to good use .
     
  14. Dillon Hill

    Dillon Hill Member

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    Just thought I'd let you know. I was talking to the mechanic that I bought the tranny from and explained the situation to him. First he said to never use synthetic oil in these gear boxes, (various reasonsn one being it isn't great for the seals) and second, to put staight 90 weight oil in it. So I followed his advice and lo&behold I no longer have the issue. Granted I haven't been out in 100* weather yet, but have been in the 80's. Also said to make sure to run oil with zddp in it. Took his advice here too.
    Any thoughts?
    Mike
     
  15. vwnate1

    vwnate1 Member

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    Success !

    Good deal ;

    I still recommend the synthetic gear oils for the same reasons , it improves shifting and reduces grinding .

    As long as you're happy now , leave well enough alone .

    Remember : regardless of actual miles driven , you must drain and re fill the tranny every 12 months .
     

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